Top part of GBIC case, so that the tiny expensive things are protected.
Use customizer for your perfect fit size.

Bottom part is https://www.thingiverse.com/thing:3809579

Customizer links:
Top part: https://www.thingiverse.com/apps/customizer/run?thing_id=3809688
Bottom part: https://www.thingiverse.com/apps/customizer/run?thing_id=3809579